JPS5935552B2 - In-line gun color - cathode ray tube convergence device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a convergence device for an in-line gun color cathode ray tube, and in particular to a convergence device for an in-line gun color cathode ray tube, in particular, it is configured to correct spot distortion of an electron beam at the same time as correcting misconvergence.

In this application, 1 is an example of an inline gun color cathode ray tube.
A one-gun, three-electron lens, and three-beam cathode ray tube will be described.

What is shown in Figure 1 is an outline of the internal structure of a 1-gun 1-electron lens 3-beam cathode ray tube. 1 is an electron gun (cathode) as a beam generation source, and the three muzzles 1a, Ib of this electron gun 1 are
Red, green (q), and blue (B) beams are emitted from Ic and Ic, respectively.

These beams are focused by electron lenses 2, 3, and 4. Then, the electrostatic convergence device 5 performs static convergence adjustment, and the electromagnetic convergence device 6 performs dynamic convergence adjustment, and these beams are transmitted through an aperture grille 7 to a striped three-color phosphor 8. Hit it. These equal beams R, G, and B are mainly deflected by a horizontal deflection coil 9. FIG. 2 is an enlarged view of the electrostatic convergence device 5 and the electromagnetic convergence device 6 seen from the muzzle of the cathode ray tube.As shown in FIG. It consists of plates 5a, 5b, 5c and 5d. Then, the high voltage from the high voltage transformer 10 is rectified by the high voltage rectifier circuit 11 composed of a diode and a capacitor, and the deflection plate 5b
and 5c, and the voltage applied to the deflection plates 5b and 5c is divided by the variable resistor 12 and applied to the deflection plates 5a and 5d. Input terminal 6 of electromagnetic convergence device 6
Parabolic currents synchronized with the vertical period are supplied to a and 6b. Conventionally, when adjusting the electrostatic convergence using the electrostatic convergence device 5 shown in FIG.
2, the convergence was properly aligned at the center of the screen as shown in Figure 3A. Here, the solid line shows the bright line of the green beam G, the broken line shows the bright line of the red beam R, and the dashed line shows the bright line of the blue beam B. When performing dynamic convergence adjustment, the vertical period is parabolic, as shown in Figure 3B, where the correction amount is zero at the center in the vertical direction and the correction amount d becomes large at the upper and lower ends of the vertical direction. A correction current of 1 is passed from terminal 6a to 6b of the electromagnetic convergence device. However, in the diagram +
The symbol indicates that current flows from terminal 6a to 6b.
The symbol 1 indicates that current flows from terminal 6b to 6a. This correction current moves the bright line of the blue beam B and the bright line of the red beam R as shown by the arrows in FIG. 3A to perform dynamic convergence adjustment. However, in such a case, the main deflection magnetic field produced by the horizontal deflection coil 9 and the magnetic field produced by dynamic convergence strengthen each other at the upper and lower ends of the screen in the vertical direction, thereby promoting spot distortion as shown in FIG. 3C. In view of the above-mentioned points, the present invention seeks to eliminate such drawbacks.

An embodiment of the present invention will be described below with reference to the drawings.

In the present invention, as shown in FIG. 4A, the variable resistor 1 is adjusted so that the static convergence is properly matched at T1 and T2 between the vertically upper and lower edges of the screen and the vertical center.
Adjust 2.

Note that the correction amount D2 to be corrected by dynamic convergence at this time is smaller than the correction amount d1 in FIG. 3A. Then, as a correction current of the electromagnetic convergence device 6 that adjusts the dynamic convergence, as shown in FIG.
And at T2, the correction current becomes zero, and the top of the screen in the vertical direction,
At the lower end, a large correction current is passed from terminal 6a to terminal 6b of electromagnetic convergence device 6. Then, at the vertically upper and lower ends of the screen, as shown by the arrows on the screen in Figure 4A, the bright line of the blue beam B is deflected to the right and the bright line of the red beam R is deflected to the left on the screen to perform dynamic convergence adjustment. . Also, Figure 4B
As shown in the figure, a large correction current is passed from the terminal 6b to the terminal 6a of the electromagnetic convergence device 6 at the vertical center of the screen to deflect the bright line of the red beam R to the right and the bright line of the blue beam B to the left. Make convergence adjustment. At this time, the waveform of the current flowing through the electromagnetic convergence device 6 becomes a parabolic current as shown in FIG. 4B. By performing dynamic convergence correction in this way, the magnetic field due to dynamic convergence at the top and bottom edges of the screen can be weakened, as shown in Figure 4C, so the amount of correction magnetic field superimposed on the vertical deflection magnetic field is reduced. , spot distortion is reduced compared to the conventional example.
Since the present invention is configured in this way, it is possible to prevent spot distortion from becoming excessive when correcting misconvergence.

In another embodiment of the present invention, as shown in FIG. 5A, the static convergence is adjusted to match at the upper and lower ends of the screen, and as shown in FIG. 5B, the correction amount D3 is adjusted at the upper and lower ends of the screen in the vertical direction. Dynamic convergence adjustment may be performed by flowing a correction current from the terminal 6b of the electromagnetic convergence device 6 to the terminal 6a such that the correction amount becomes zero and the correction amount becomes large at the vertical center of the screen.

In this case, since the correction magnetic field at the upper and lower ends of the screen is zero, no distortion is generated by the correction magnetic field at the upper and lower ends of the screen. In this case, the strength of the correction magnetic field is maximum at the center of the screen, but
Since the main deflection magnetic field, which is the main cause of spot distortion, is zero at the center of the screen, the final spot distortion is small.

[Brief explanation of drawings]

Figure 1 is an overview of the internal structure of a 1-gun, 1-electron lens, 3-beam cathode ray tube, Figure 2 is the main part of Figure 1, and Figure 3 is for explaining the convergence device of a conventional in-line gun color cathode ray tube. FIG. 4 is a route map for explaining one embodiment of the in-line gun color cathode ray tube convergence device according to the present invention, and FIG. 5 is a route map for explaining another embodiment of the present invention. It is. 5 is an electrostatic convergence device for static convergence adjustment, and 6 is an electromagnetic convergence device for dynamic convergence adjustment.

Claims (1)

[Claims] 1 Adjust the static convergence of the inline gun color cathode ray tube so that it matches the vertically upper and lower ends of the screen and the vertical center, respectively, or at the vertically upper and lower ends, and then The correction amount becomes zero near or at the top or bottom of the vertical direction, and the top or bottom of the vertical direction becomes zero.
An in-line gun color cathode ray tube characterized in that dynamic convergence adjustment is performed by supplying a parabolic correction current synchronized with a vertical period such that the correction amount is large at the bottom end and the vertical center or at the vertical center. convergence equipment.